The present invention pertains to means for selectively raising working brushes of a cleaning appliance such as a vacuum cleaner, rug shampooer, floor polisher or the like. Vacuum cleaners are exemplary of such common floor cleaning appliances employed universally in home and business. The primary vacuum nozzle through which debris is passed typically includes a beater brush to aid in the removal of debris from a carpet. The beater brush is designed to rotate at a high speed so that its bristles engage and agitate the carpet fibers, and help pull the debris therein up into the primary vacuum nozzle. The cleaning of the carpet is generally accomplished by moving the vacuum cleaner along the floor surface until it has been thoroughly vacuumed.
There are times, however, when the vacuum cleaner continues to run, but is left stationary at one location on the carpet; such as when a user interrupts the vacuuming operation temporarily or is employing off-floor vacuuming accessories on nearby furniture or the like. If the primary vacuum nozzle with its beater brush is kept in its operative position in such a situation, the brush would tend to cause excessive wear on that location of the carpet. In an effort to obviate this problem, prior artisans have employed a variety of assemblies which operate to lift the primary vacuum nozzle with its beater brush up away from the carpet, so that the brush is allowed to rotate without engaging the carpet.
Numerous arrangements have been developed to facilitate the lifting of the primary vacuum nozzle. Some devices have employed foot pedals for selective actuation by the user; other devices are provided with mechanisms which are actuated by the attachment of vacuuming accessories; and still others are provided with means which are mechanically coupled to operate through movement of the vacuum cleaner's handle. However, these mechanisms require the user to perform affirmative additional steps to thereby raise the beater brush and/or employ complicated mechanical linkages to effect the lifting motion.
Further, any lift-off mechanism requires provisions that will lock it into its lifting position, so that the beater brush may be maintained above the floor surface. These locking arrangements are invariably, out of necessity, integrally tied to the manner in which the lift-off mechanism is actuated. Consequently, the locking arrangements typically incorporate the same deficiencies as previously cited; specifically, the usage of complicated linkages, additional affirmative user actions, or the attachment of accessory items. Hence, the need exists for a compact, efficient locking assembly that will not require additional user actions or be subject to disrepair due to multiplicity of parts.
Locking assemblies for locking handle structures in their storage positions are used extensively in the industry. These assemblies have taken on many forms. However, these are not of a compact, durable nature and/or are not tied in with the locking of the lift-off mechanism.